Can washing system



May 22, 1956 R. E. FARlsoN CAN WASHING SYSTEM 4 Sheets-Sheet l Filed Jun 25, 1952 May 22, 1956 R. E. FARISON CAN wAsHING SYSTEM 4 Sheets-Sheet 2 Filed June 25. 1952 ve?? 07" ,QW

May 22, 1956 R. E. FARlsoN CAN WASHNG SYSTEM 4 Sheets-Sheet 3 Filed June 25, 1952 May 22, 1956 R. E. FARlsoN CAN WASHING SYSTEM 4 Sheets-Sheet 4 Filed June 25, 1952 CAN wAsHING SYSTEM Robert. E. Farison, Chicago, Ill., assignor to The Diversey i Corporation, a corporation of Illinois t Application June 25, 1952, serial Na. 295,446 14 Claims. (CI. 134-i-56) This invention relates to a washing system and more particularly to a liquid spray type washing system includ-- i ing an improved hydraulic dspenser. j i

In liquid washing systems and particularly the industrial types, as for example those used'in dairies and bottlng plants which employ spray jets or nozzles, the washing liquid is discharged from the nozzles under pressure and these nozzles are usually intermittently and repeatedly turned off and on. It is important in such systems that the washing liquid supplied to the nozzles be maintained at the desired solution strength during continued operation.

This invention provides an economical vand greatly improved washng system whereby apredetermined amount of stock solution is automatically drawn into an improved liquid or hydraulic dispenserunit during the period when Washing liquid is not being discharged from the spray nozzles and emptied from the dspenser unit into the washing liquid during the period when washing'liquid is being discharged from the nozzles. In this way the Washing liquid is maintained at the desired, constant solution strength during continued operation of the washing system.

The invention will be described with reference to an embodiment illustrated in the accompanying drawings, in which:

Fig. 1 is a side elevational view of a spray washing system embodying this invention, partially broken away to show the position of the spray nozzle and the object to `be washed;

Fig. 2 is a fragmentary, enlarged side elevational view of the liquid dspenser and the stock solution container of Fig. 1, partially broken away to show the location of the inlet pipe line leading from the stock solution to the dispenser unit;

Fig. 3 is an enlarged, fragmentary top plan view of the liquid dspenser unit and stock solution container of Fig. 1;

Fig. 4 is an enlarged, fragmentary Vertical sectional `view of the liquid dspenser unit of Fig. l;

Fig. 5 is an enlarged, fragmentary Vertical sectional view of the head element of the dspenser unit of 'Fig. l show- .ing the ducts and ball check valves in dotted lines;

Fig. 6 is an enlarged, fragmentary top plan view of the dspenser unit of Fig. 1;

Fig. 7 is a fragmentary, sectional view taken substantially along line 7-7 in Fig. 5;

Fig. 8 is a fragmentary, lsectional view taken substantially along line 8-8 in Fig. 5;

Fig. 9 is a side elevational view of a spray Washing system embodying this invention but different from the Washing system in Fig. 1 and partially broken away to show the position of the spray nozzle and the object to be washed; p

Fig. 10 is a top plan view of the washing system of Fig. 9; i

Fig. 11 is an enlarged, fragmentary Vertical sectional view of the liquid dspenser unit of Fig. 9;

Fig. 12 is a fragmentary, top plan view of the liquid dspenser unit of Fig. 10;

` tube 36 to the desired position.

g s 2,746,465 I Patented Mayf22, 1956 ICC Fig. 13 is a fragmentary, sectional view taken substan- `tially along line 13-13 in Fig. 12.

intake side of a pump 24 and from the discharge side o'f this pump to a spray nozzle or jet 25 positioned within the confines of the tank Vside walls above the level of the washing liquid 21. lA standard type whistle valve l28 is connected in the supply pipe line 23 between the pump 24 and the spray nozzle 25 to intermittently and repeatedly turn the spray nozzle' off and on; The pump 24ocauses washing` liquid to fiow from the tank through the supply pipe line 23 to the spray nozzle under pressure and the spray nozzle as here shown is directed upwardly so that spray therefrom is directed against an inverted metal directly above the spray nozzle. i

An hydraulic or liquid dspenser 29 automatically supplies a predetermined amount of stock solution 30 from a container 31 filled with this solution to the washing liquid 21 in the tank 20 during each period when the spray nozzle 25 is Operating. As here shown, the stock solution container 31 is positioned in a frame 32 above the spray nozzle 25 but outside the washing lliquid tank 20 by means of a support bracket 33 secured to the bottom of the frame. The dspenser unit 29 is held in'an upright position adjacent the stock solution container 31 by a support member 34 secured to one side of the frame 32.

Referring to Figs. 1, 2 and 4, the liquid dspenser unit 29 includes an upright metering tube 36 and a` head v fixedly mounted on the top end portion of this tube. An actuating pipe line 37 connects the bottom end of the metering tube 36 with the spray nozzle 25 so that Washng milk can 27 mounted by means of support members 26 liquid under pressure exerted by `the pump 24 is supplied `simultaneously to the spray nozzle and the bore of the metering tube. A piston`38 is sldablytmounted in the bore of the metering tube and its length of stroke is determined by a piston stop 39 having a bore` therethrough upwardly. As here shown, the top portion of the seating unit hole is tapered and a ball check 41 mounted on the bottom surface of the piston fits into this tapered portion i When the piston is at the bottom of its stroke, thereby sealing the hole of the seating unit.

An O ring seal 42, mounted in a grooved ring about the outer surface4 of the seating unit also binds against the inner surface of the metering tube wall.` This seal allows the tapered seating unit 40 to be moved along the bore of'the metering tube and holds it in position. Thus, the piston stroke can be adjusted to the desired length. As here shown, the bottom portion of the bore ingthe seating unit 40 is threaded so that an adjustment rod not shown in the drawings can be inserted at theV bottom Vof the metering tube, screwed into the threaded portion, and the seating unit 40 then moved along the metering In addition, the O ring seal 42 prevents washing liquid from fiowing past the seating unit 40, except through its hole. s

It is important to note that the piston 38 has sufliciently close clearance with the inner wall of the metering tube 36 so that essentially no washing liquid moves past the piston from below while it is moving upwardly. Howvftion of the metering tube 36.

the top..of.the vstroke,andmpressure vis still Wbeing.maintained by the pump 24 on the washing liquid in both the actuating and the supply pipe lines. In this way, the .actuating pipe line`37 is` automatically' primed.l

Referring to Figs.-4"to 8, the head 35 of thedispenser unit is here shown'fixedly mounted onfthertop end por- 43', oneend of which communicates with the bore of the r h etering tube 36, a.discharge duct 44, one end of which also -communicatesfwith' the bore of the 'metering tube, -=an d aport duct 45, opening to the atmosphere and communicating with t he discharge duct 44. 'A ball check 1x='va`. l've, -'f-as 4`6,-is'loeatedin each 'of.the ducts and'fthe 1s ``adapted to move vertically twa'rd and away fi'bni its tapered -valve-seat, th us opening and closirig` the diicts in a iman-ner'described-hereinafter. An inlet pipe line 47 Elleads fror'nlthef'otherend Tof the inlet duct. into the stock vvsolution 30located inthe container'f 31 and .a discharge -pipe-lineAS-leads from the other end of theduct 44 into A''the tank 20,' emptying at a point above the level of the vashing liquid'contained therein; t i

'ji-'It is importantthat the container 31 holding'the stock ifsolution-and-the dispenser unit 29 be so positioned that the outlet port 44 a .of the' discharge duct 44 is above the '-:highes' t'-po ssible level-of the stocksolution. Thus,'in the {f'enibodiment'shwnjtheoutlet port 44a is above the -3 eveli;Qf'thestopkvsolution in the container and not "elhw'theilevel vof the highest point of the inletpipe line hrough the "di spenser head 35 into the dischargepipe f=1ine348 irrespectivefof vthe piston action because'of pos- *"sible siphoni'ngf'; Thisjis'readily achieved by positioning "the 'top endof'the metering tube 36 above the level of 'stock solution in the container 31.

The general; method of operating the washing.` system sfiasfollowszzDuring operation of the washing system the'pump'124 operates continuously. However, the V5`*-'v vhis`tle`*valve 28 intermittently and repeatedly opens and f `closes.'"jDuringthe period that the whistle valve is open, f shingliquidunderjpressure exerted by the Vpump 24 dischargedfrom the spray nozzle 25 and at the same '*'time a 'p'ortion of this liquid flows past the spray nozzle LJ'intothe:actuating pipe line 37 and against the bottom js'ui'face'offthe piston 38.` As a result, the piston is forced '*=pwar"dly,'to"the' piston stop 39 and the amount of stock i' 'solution in the bore. of the metering tube above thepiton 'is'foreedfthrough'the discharge duct 44 and the discharge ipe line- 18 into the washing liquid in the tank .20. Durhis'i'pei'iod of operation, .the inlet ball check valve reinainsclosedand thefdischarge ball check valve open. eilf' the;'stock"solution is.being discharged against anyhack F''essure'in'the Klischargepipe line 48, the Vport duct ball ft'hezc'k valve'is'closedtagainst back flow. Ontheother 1`ha13idg' if'the're'is little or nohackpressurejn the discharge pipe line, but'a'vacu'um is created in this line, as ''-foi' 'eX'ample if any ysiphoning action occurs as a result fip'rimin'g bythe charge of stock solution discharged i i into 'the dischargepipe line from the bore of the metering tube 36, the port duct check valve opens allowing air to le *draw'ri into the discharge pipe line, thereby breaking 'ftleresultin'gl siphon action. It is important to prevent i'''tl`1e`''iccurjrence of such siphoning action as stock solution ;'wouldfbe draw'n from the stocksolution container 31 fi 'espective'of the piston action.

' When" the piston '38'comes to rest at the top of the s't'ok'ela'small quantity of washing liquid below the piston flnshes pfast'itas' th'epressure continues to be applied to *"ithel'wshing" liquid in the actuating pipe line for a short period of time thereaftenf In this way the actuating pipe f-li'rie` 37518' automatically primed. V i

`During the period that the whistle valve28 remains **closed, 'pressure is Ano longer exerted by thepump-24 'jthroughfthe washing liquid in the actuating pipe line37 andbth'el spray nozzle -25 is not Operating.w Inview of 7.511 Stock-solution is; thereby prevented from liowing lt contains an inlet duct this and because the stock solution container 31 is above the ,level .of the. spray. nozzle..25, the washingliquidtin the bore of the meteringY` tube 36 below the piston 38 drains downwardly back through the actuating pipe line and out through the spray nozzle 25. The resulting drainback head causes stock solution in the container 31 to be drawn through theinletpipe line 47 and the inlet duct 43 into the bore of the metering tube 36 above the piston. The dischargeball check Valve remains closed against back fiow during this period and the inlet ball checkivalve is open." ,'Theportcheckalvewill open to the atmosphere if any vacuum is` created in the discharge pipe line-18, as for example by .the occurrence of siphoning action therein. The piston 38 moves downwardly with the flow of stock solution into the bore of the metering tube 36 and acts as a Separator between the washing liquid below the piston and stock solution above it. When the piston comes to rest on the seating unit 40, drainback stops and no more stock solution is drawn into the metering tube. The stock solution present'in the bore of vthe metering tube 36 above the piston 38 is'then forced'out through the discharge duct 44 and the discharge pipe line 48 into the'tank 20 when the whistle valve opens 'and pressure is again applied to the lwashing liquid,iiihthe vactuating pipe line 37. Thus, adjusting the length ofethe piston stroke determines the amount of stock solution which 'is supplied to the washing liquid fo:r each complete cycle of the whistle valve. v

The dispenser unit may be constructed of any material having suitable mechanical and corrosion resistant properties. When used in conjunction with'bottleiwashing systems it may be made of suchfmaterial as methyl methacrylate resin and the ball checks of nylon.

Another form of the washing system embodying the basic principles of this invention is illustrated inFigs. 9 to 13. i

Using reference numerals 100 higher for'convenience of correlation of the parts with the previous'jdescription of the washing system shown in Figs. l to 8, it w ill be seen that the system again includes a tank |1 20` ,c2'ntaining washing liquid 121. A side wall of this `tfa nk has an opening 122 near the bottom and one end of asjlpply pipe line 123 is connected to the side wall'` align- 'ment with this opening. As in the washing system of 12811 s connected in the supply' pipe line between the whistle valve 123 and the spray nozzle,1 2.'}.y This thi'otvtling valve is adjusted so that apresure drop; of several pounds ,per square' inch isf developed thereae`ros's'.when

` thefwhistlevalve is open and washing liquid under presv`sure is'beingv discharged fromthe spray nozzle;

An hydraulic or liquid dispenser 129 automatically 'Supplies' a predeterinined amount ofstockV solution 130 from a container 131 filled wi t l1 this solution to thejsupply'pipe line 123 at a point between "the thrott1in`g`yalve 12 8 l and the spray nozzle IZSduringeachperiod Vthat the spray'no'zzle 125 is operating. As here shown," the stock solution container 131 is -'positioned above vthe lefvel 'of *the spray nozzle 125 but outsidethe washing liquid tank M120 and the vdispenser unit 129 is held in an upright posi- 'tion adjacent'the stock solution container 131.` i

`Refe'ring to Figs. 'll to' 13; theliquid dispenser'jinit 129 is very similar to the liquid dispenser unit inth p` ously described washing system and operates in identical manner. It also includes an upright meteringt'ube solution.

interior portion of vthe tube and' head readily cleaned. As here shown, this is aecomplished by having the bottom portion of the head in the Shape of a plug which fits inside the top bore portion of the metering tube. An ring seal 149 about the plug shaped portion of the head binds against the inner surface of the metering tubewall and aids in rigidly holding the head in position and preventing liquid from flowing out of the metering tube between the inner wall of the tube and the plug portion of the head.

An actuating pipe line 137 connects the bottoni end of the metering tube 1'36 with the supply pipe line 123 at a point between the whistle valve 128 and the throttling valve 128z. By adjusting the throttling valve so that a pressure drop of severalpounds per square inch develops thereacross when the whistle valve 128 is open and the spray nozzle is Operating, a suflicient pressure differential is created to cause washing liquid from the supply pipe line 123 to flow into the actuating pipe line 137 under pressure and actuate a piston 138 which is slidably mounted in the bore of the metering tube. The length of stroke of this piston is determined by the bottom of the dispenser head 135` extending into the bore of the metering tube 136 above the piston and a seating unit 140 identical in structure with that described in the previous washing system.

As in the previously described dispenser unit, the piston 138 has sufliciently close clearance `with the inner wall of the metering tube 136 so that essentially no washing liquid moves past the piston from below while it is moving upwardly. However, the clearance between the piston and the inner wall of the metering tube is such as to permit a small amount of liquid from below the piston vto flow past it when it is at rest at the top of the stroke and pressure is still being maintained on the Washing liquid in both the actuating and supply pipe lines.

The head 135 of the dispenser unit here shown is similar to that in the previously described washing system. It contains an inlet duet 143, one end of which communicates with the bore of the metering tube 136, a discharge duct 144, one end of which also eommunicates with the bore of the metering tube,` and a port duct 145 opening to the atmosphere and eommunicating with the discharge duct 144. A ball check valve, as 146, is located in each of the ducts and the ball is adapted to move vertically toward and away from its tapered valve seat. An inlet pipe line 147 leads from the other end of the inlet duct into the stock solution 13h located in the eontainer 131 and a discharge pipe line 148 leads from the other end of the duct 144 into the supply pipeliue 123 between the whistle valve 128 and the throttling valve 128g.

As in the previous vWashing system container 131 holding the stock solution and the dispenser unit 129 are so positioned that the outlet port 144mv of the discharge duct 144 is above the highest possible level of the stock Thus, in the embodiment shown, the outlet port 144a is above the level of the stock solution in the container 131 and not below the level of the highest point of the inlet pipe line 147.

The general method of Operating the washing system of Figs. 9 to 13 is as follows: During operation of the washing system the pump` 124 operates continuously. However, the whistle valve v128 intermittently and repeatedly opens and closes. During the period that the whistle Valve is open washing liquid under pressure exerted by the pump 124 is diseharged from the spray nozzle 125. By proper adjustrnent of the throttling valve so that a pressure drop of several pounds per square inch is developed thereacross, the resulting pressure differential is sufiicient to force a portion of the washing liquid in the supply pipe into the actuating pipe line 137 and' against the bottom surface of the piston 138. As a result, Vthis piston is forced upwardly to the top of the metering tube 136 and the amount of the stock solution in the bore of the` metering tube above the piston is forced through the stock solution is being discharged against back'pressure.

in the discharge pipe'line 148 and the port duct ball check valve remains closed against back flow. The inlet ball check valve also remains closed and the discliarge ball check valve is open. i f

When the piston 138 comes 'to rest at the top ofthe stroke, a small quantity of washing liquid below the piston flushes past it as the pressure continues to be applied to the washing liquid in the actuating pipe line 137 for a short period of time thereafter. In this' way the actuating pipe line 137 is automatically primed.

During the period that the whistle valve 128 remains closed, pressure is no longer exerted by the pump 124 through the washing liquid in the actuating pipe line 137 and the spray nozzle 1.25 isnot Operating. In view of this and because the stock solution container 131 is above 'the level of the spray nozzle 125, the washing liquid in the bore of the metering tube 136 below the piston 138 Vdrains downwardly back through the actuating pipe line 137 and out through the spray nozzle 125. The resulting drainback head causes the stock solution in the container' 131 to be drawn through the inlet pipe line 147 and the inlet duct 143 into the bore of the metering tube 136 above the piston. The discharge ball check valve remains closed against back flow during this period, and the inlet ball check valve is open. The port check valve will open if any vacuum is created in the discharge pipe line 148, as for example by theoccurrence of siphoning action 'therein The piston 138 moves downwardly with the flow of stock solution into the bore of the metering tube 136 and aets as` a Separator between the washing liquid below the piston and the stock solution above it. When the piston comes to rest on the seating unit 141), drainback stops and no more stock solution is drawn into the metering tube. The stock solution present in the bore of the metering tube 136 above the piston 138 is then discharged into |the supply pipe line during the period when the whistle valve remains open in theV manner previously described.

Although not shown in the drawings, the supply pipe line 123 may be connected to a tap water outlet instead of pump 12.4. Under such conditions the pressure comes from 'the tap water supply which serves to actuate the `liquid dispenser 129.

scribed is actuated by pressure exerted by a pump through recycling the washing solution 121 in the tank 120, it may be actutated by a separate pressurersource, as forexample by a separate pump or from pressure supplied from a tap water outlet. A cycle timer and solenoid valve may be connected to the liquid dispenser in an appropriate manner obvious to those skilled in the art to cause the dispenser to operate'in the manner described above.

Having described the invention as related =to the embodiment shown in the accompanying pdrawings, it is intended that the invention be not limited to any of the details of description unless otherwise specfied; but rather be construed broadly within its spirit and scope as set out in the accompanying claims.

I claim:

1. In a washing system a source of washing liquid; means for discharging the washing liquid; a supply pipe line leading from the washing liquid source to the discharging means; means for supplying the washing liquidl ..A-;flow of stock 'solutionthrough theinlet pipe, line into the 2346,485 7 8 ,of-lthelubeV element..-wi th-the-discharge 'means; an inlet vduct'and open when a vacuum is created in the discharge f-'PPG 'fiht'i- Ii the Stackv Solution Sourcetwith ;the fdu l,tube element;-afstock 'solution'discharge pipe line leading I 'fr'omthetubefele'ment above the highestpossibleleyelof check'valves areballs adapted to move substantially i V v vertically toward and .away from .a valve seat to open and -\-the stock solution,-sad dischargepipe line emptying into- 5, i; i A ;Wthefwashing liquid; fiow regulating means in said discharge CIOSC'th,ed 11(=t $.V pipe .line and said inlet pipe line adapted to permitthe .w 7. A waShmg'SYStem as' SCi forth In Clalmi5 '111 Whlch t means is provided forV varying the length of travel of the piston in the boreof the tube element. v

8. The washing system as set forth in claim 5 in which the clearance of the piston with Athe inner wall of the tube element is adlapted to prevent the flow of substantiall'y. any washing liquid in the actuating pipe line below the piston to flow past the piston during its upstroke, and permit a small amount of the washing liquid to -flow past the piston When it is at rest at the top of the stroke and pressure is still being maintained -by the pumping means on the washing liquid in the actuating pipe'line.

9.- In a washing spray system a container for holding washing liquid; a nozzle for spraying lthe washing liquid .boreof- 'the `tube element above the piston during downi fstrokerdf-the, pist0nand to permit -the flow of stock solu- '10 t'iornin the borev of the tube elementfin'to the stock solu- 'ftin diqherszpipczline during -upstrpke of the. piston un- "der the influence'of-,Vwashing liquid pressure in the actuatingpipe line' xsrtd by the; washing .liquid Supply eans.l f i i 2.1 Ths'washingsystm as 'Stetffqrthin claim 1 in which ;vthe stock- ,solution .discharge pipe line empties into the `rffwashing `liquid above `the-level of-the-washing liquid and .inthe'absence of substantially any back pressure in the fdischarge pipe line.

g 3. The washing system as set forth in claim 1 in which thesupply pipe line has a pressure diferential' means r voperativel'y connectedltherewith located-between the dis- ,fcihar-ge means and the means for intermittently and repeatedlyapplying and then releasing the pressure exerted by the pumping meanson the washing liquid, the discharge t means and the end of the stock solution discharge pipe i lineemptying into the washinglliquid being connected to the supply pipe line on the low pressure side of the pressure dilferential means and one end-of the-actuating pipe ,line being connected to thesupply pipe line on` the high Vpressure side of the pressure differential means. .4. The washing system as set forth in claim 3 in which the means for intermittently; and repeatedly applying and then releasing the pressure exertedby the pumping means v .onthe .washing liquid is a whistle valve connected in the .Lsupply pipe line and the pressure diiferential means is e a throttle valve-connected in the supply pipe line.

5. In a washing system a source of washing liquid; means for discharging the washing liquid; a supply pipe line leading from the washing liquid sourceto the dis- ;charge means; means forpurnping `the, washing liquid through the supply pipe line under pressure from the i source to the dischargeZirneans; means for intermittently andrepeatedly `applying `and then releasing the pressure exerted by the pumping means on rthe washing liquid in I the supply pipe line; a-container for holding stock solu- -tion positioned` above thet discharge means; a liquid dispenser including a substantially upright tube element hava liquid actuatedpiston slidably mounted in its'bore, ahead element on the top end of the tube element, an '.actuating pipe' line connecting the bottom end of the `.tube element with the discharge means, an inlet duct in the head element cortununicating with said bore, an inlet pipe lineleading-from the stock solution container to the inlet duet,` a discharge-duet; in the head element communicating with said bore, the `ro utlet port of said discharge duct being above the highest possible level of the stock -solution,-a--stock solution discharge pipe line lead- ,..ingfromthe discharge'duct and'emptying into the Wash-V ing liquid, a port duct opening to 4the atmosphere and communicating with the discharge duet, and a check valve -:operatively positioned' in each of. said ducts, the inlet check valve being adapted to be open and the discharge check valve to be closed during the down stroke of the piston to" permit the flow of stock solution through the inlet 'pipe' line and the inlet duet into the bore above the piston, and the inlet check'valve to be closedland the f discharge check lvalve tobe open during the upstroke of, the pistonunder the influence of washing liquid pressure in the lactuating pipe line exerted byl the pumping means to permit the flow of stock solution from said bore through oirt heck valve being closed against an object; a supply pipe line leading from-the Washing liquid container torthe nozzle; means for pumping the Washing liquid through the supply pipe line under pressure from the washing liquid container to the nozzle; a whistle valve connected in the supply pipe line for intermittently and repeatedly applying and then releasing pressure exerted by the pumping means on the washing liquid in the supply pipe line; a container for holding stock solution positioned above the level of the nozzle; a liquid dispenser including a substantially upright tube element with its top end above the level of the stock solution and having a liquid actuated piston slidably mounted in its bore, a head element on the top end of the tube element, an actuating pipe line connecting the bottom end of the tube element with the nozzle, an inlet duet in the head element communicating with said bore, an inlet pipe line t leading from the stock solution container to the inlet w and a check valve operatively positioned in each of said ducts, the inlet check valve being adapted to be opened and the discharge check valve to be closed during the downstroke of the piston to permit the flow of stock solution through the inlet pipe line and the inlet duct into the bore above the piston, and the inlet check valve to be closed and discharge check valve to be open during the upstroke of the piston under the infiuence of washing liquid pressure in the actuating pipe line exerted by the pumping means to permit the flow of stock solution from said bore through the discharge duct and the discharge pipe line into the washing liquid container, the port check valve being closedl during the existence of any back pressure in the discharge duet and open when a vacuum is created in the discharge duct.

10. The washing spray system as set forth in claim 9 in which the check valves are balls adapted to move substantially vertically toward and away from a valve seat to open and close the ducts.

ll. The washing spray system as set forth in claim 9 in which the bore of the tube element contains a piston seat adapted to be positioned along the length of said bore to vary the length of travel of the piston in the bore, said seat having a hole therethrough andtthe piston having a ball check valve secured to its bottom surface and positioned to seal said hole when the piston is at the bottom` of its downstroke.

12. In a washing spray system a source of washing liquid, a nozzle for spraying the Washing'iliquid against an object; a supply pipe line leading'from the washing liquid source to the nozzle; means for supplying the Washing liquid through the supply pipe line under'pressure from the washing liquid source to the nozzle; Valwhistle valve connected in the supply pipe line for intermittently and repeatedly applying and then releasing pressure ex- `erted by the washing liquid supply means on the washing liquid dispenser including a substantially upright tube element with its top end above the level of the stock solution and having a liquid aetuating piston slidably mounted in its bore, a head element on the top end of the tube element, an actuating pipe line leading from the bottom end of the tube element to the supply pipe line between the whistle valve and the pressure differential means; a port duet opening to the atmosphere and communcating with the discharge duct, an inlet duet in the head element communicating with said bore, an inlet pipe line leading from the stock solution container to the inletduet, a discharge duet in the head element communieating with said bore, a discharge pipe line leading from the discharge `duct to the supply pipe line between the pressure differential means and the nozzle, the nozzle and the end of the discharge pipe line connected to the supply pipe line being on the low pressure side of the pressure diiferential means, a port duet open to the atmosphere and communicating with the discharge duet, and a check value I i operatively positioned in each of said ducts, the inlet check valve being adapted to be opened and the discharge check valve to be closed during the down stroke of the piston to permit 'the flow of stock solution through the inlet pipe line and the inlet duct into the bore of the tube element above the piston and the inlet check valve to be closed and the discharge check valve to be open during is created in the discharge duct.

13. The washing spray system as set forth in claim 12 in which the check valves are balls adapted to move substantially vertically toward and away from a valve seat to open and close the ducts. i

14. The washing spray system as set forth inclaim 12 in which the bore of the tube element contains a piston seat adapted to be positioned along the length of said bore to vary the length of travel of the piston, said seat having a hole therethrough and said piston having a ball secured to its bottom surface and positioned to seal said hole when the piston is at the bottom of its down stroke.

References Cited in the file of this patent UNITED STATS PATENTS 

